Description
Improper Neutralization of Escape, Meta, or Control Sequences vulnerability in Apache HTTP Server through environment variables set via the Apache configuration unexpectedly superseding variables calculated by the server for CGI programs. This issue affects Apache HTTP Server from 2.4.0 through 2.4.65. Users are recommended to upgrade to version 2.4.66 which fixes the issue.
Affected products
apache: http server
References2
- httpd.apache.org/security/vulnerabilities_24.html Vendor Advisory
- www.openwall.com/lists/oss-security/2025/12/04/7 Issue TrackingThird Party Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 1% percentile: 59 · as of 11 November 2026
- CWE
- CWE-150
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